refactor: move transcripts into core

Move meeting notes into core transcripts, remove the bundled meeting-notes plugin/API, and require explicit transcripts.enabled before exposing the recording-capable tool.

src/cli/program/core-command-descriptors.ts

@@ -71,6 +71,11 @@ const coreCliCommandCatalog = defineCommandDescriptorCatalog([
     hasSubcommands: true,
     parentDefaultHelp: true,
   },
+  {
+    name: "transcripts",
+    description: "Inspect stored transcripts",
+    hasSubcommands: true,
+  },
   {
     name: "agent",
     description: "Run one agent turn via the Gateway",